This invention relates to inflatable devices for supporting a body. The invention is especially applicable in the field of disposable inflatable mattresses, mattress overlays, seat cushions, and back supports, particularly those used for home-care, long-term care and hospital use.
Inflatable mattresses for people to lie or sleep on are well known in the prior art.
Generally speaking, such mattresses and cushions, when used for medical applications, are used by immobilized patients. Various types of these mattresses purport to provide a reduced pressure on the body and/or relieve pressure in specific zones or on specific parts of the body. The materials of manufacture of these mattresses generally do not allow water vapor produced by the person""s perspiration or condensation to escape from the vicinity of his body, thus requiring an additional item to be placed between the patient and the support surface.
In addition, inflatable mattresses of the prior art are generally configured so that their construction requires a large amount of labor, usually because the formation of individual air chambers that make up the entire mattress need to be connected in a way that allows the chambers to be filled with air at the time of inflation, and at the same time must be placed and configured to provide suitable support to the user. The prior art designs require a time consuming assembly and mechanical joining of material to make the mattress, and this labor intensive construction of the air mattresses makes the air mattresses expensive, and consequently unsuitable for disposable mattress applications, such as in a hospital environment where the mattress may be contaminated by contact with a patient.
It is also a problem in the prior art that if there is a rupture or loss of pressure in an inflatable mattress, the entire mattress will collapse. The result may be that, for instance, in a hospital bed, a patient might roll off the underlying bed or mattress system, or be dropped onto an uncomfortable surface below the deflated air mattress.
It is therefore an object of the present invention to provide an inflatable mattress system which has an outer layer which permits the passage of water vapor but not fluid through it, overlying and working in conjunction with a fill or batting layer which rests on an inflatable mattress underneath. The outer layer is preferably attached to the inflatable mattress as is the fill layer.
It is also an object of the present invention to provide for an inflatable air mattress of a construction such that it can be readily manufactured without undue amounts of human labor. This is accomplished by providing a mattress construction which allows for continuous formation of the mattresses as a continuous rolled out product so that each individual mattress is formed by cutting the rolled stock, and then finished with a minimum amount of additional sealing. It is also an object of the present invention to provide a method of efficient manufacture of the mattresses from continuously rolled stock.
It is further an object of the present invention to provide for an inflatable air mattress having two lateral side rail tubes which do not deflate once inflated, even if the central portion of the mattress loses air pressure.
It is also an object of the present invention to provide an air mattress wherein, even if the central portion below the patient is punctured or loses pressure, a lower set of chambers of the air mattress nonetheless remain inflated and prevent the patient dropping onto the surface of a bed, a bedspring, or another mattress below the air mattress.
It is also an object of the present invention to provide a mattress having a series of laterally extending support tubes so that adjoining supply tubes can be alternately inflated and deflated, alternatively reducing interface pressure on the body of the user.
Other benefits and advantages of the present invention will become apparent in the specification hereof, and the scope of the invention will be expressed in the claims.